Plant Population Modulate Occurrence of Green Shoulders (GS) and Internal Greening (IG) in Carrots (Daucus carota var. sativus)

Abstract

Green shoulder (GS) and Internal Greening (IG) are the physiological disorders in carrots due to chlorophyll accumulates either at the crown or internal tissues or both. GS and IG affect root quality and makes carrot roots unfit for consumption and cause a great lose to the processing industry. One of the hypothesis in our study was that plant population modulate GS and IG due to its variation in light interception. The objectives of this study were to identify the effect of plant population on the occurrence of GS and IG and establish a relationship between them. Dicer (Red core chantenay) and Slicer (Caro choice) varieties were seeded at various seeding rates. The experiment used a Randomized Block design. Each treatment was replicated four times. GS and IG were measured using a Chlorophyll meter and the output was read as Chlorophyll Index (CI). Leaf area index (LAI) was determined using a LAI-2000 Plant canopy analyzer. Carrot roots were also collected per meter for each plot. Plant population showed a significant negative correlation with GS. Correlation also existed between GS and LAI. However, plant population and LAI had poor correlation with IG in both the Dicer as well as in the Slicer varieties. It is possible that the IG may perhaps be induced prior to canopy development. Also, a poor correlation existed between IG and GS in both the Slicers and Dicers implying that one does not control other event.